As USB 3.0 gains in popularity we will begin to see it replace USB 2.0 in external storage and other devices where greater bandwidth than that provided by USB 2.0 is required. Most motherboards sold today already accommodate USB 3.0 through an add-on NEC controller. Although neither Intel nor AMD have a current chipset with native support for USB 3.0, it won't be long before that becomes available as well. And with USB 3.0 devices being backwards compatible with USB 2.0 ports, early adopters of this technology aren't stuck with a device that their motherboard and/or case do not support.

From an aesthetics standpoint, the Thermaltake BlacX 5G appears very similar to the original BlacX in appearance. It's what under the hood that differentiates it, as in addition to the USB 3.0 interface Thermaltake claims the BlacX 5G controller supports the latest SATA 6.0Gb/s drive standard. Given the sub-par performance we observed in testing, we were curious exactly what USB 3.0 to SATA 6.0 bridge controller Thermaltake was using, so we opened it up.

To our surprise we found a JMicron JMS539 chip. One thing that is interesting to note about this chip is that according to JMicron, the JMS539 only supports second generation SATA 3.0Gb/s speeds, not third generation SATA 6.0Gb/s as Thermaltake claims. The second interesting point is that the JMS539 was also used in two other USB 3.0 enclosures we've reviewed recently, the Vantec NexStar 2½" enclosure and the Sunbeamtech Airbox, and we noticed similar less-than-expected performance from both of those when using an SSD drive. As those reviews utilized a different SSD and different motherboard, the only common link between them is the JMicron JMS539. Considering our experience with this chip, we'd recommend something else such as the ASMedia ASM1051 used in the Vantec NexStar 3½" enclosure, which does support the SATA 6.0Gb/s standard.

In light of the poor USB 3.0 performance, it would be nice if the BlacX 5G also had an eSATA interface, which would allow those with high speed SSDs to be able to utilize the full bandwidth capability of their drives. On a positive note, the BlacX 5G retails for the same $60 as the original BlacX did, so at least you're not laying out any more cash than what you would for USB 2.0 support. And you will see better performance than you would with the USB 2.0 unit. But if you want to use the BlacX with a SATA 6.0Gb/s drive or a fast SSD you'd do better to look elsewhere.